Topic: Advance timing Question

[Scrubs]

I have two questions

Can static and advance timing be set independantly of each other? or are the they both set by the main plate?

reason I ask is - say my timing at idle is bang on the F with the timing light but when I open the throttle a bit
the advance moves - but moves 'too far' passed the advance marks, what would be the solution ?- if it indeed needs one
if I adjust the main timing plate to bring it back my idle timing would go out.

Also, on the points plate there are 3 screws for the main timing plate. one for adjusting points 1 and 4 and one screw for
2 and 3 but behind points plate 2 & 3 there is a 'secondary' plate with two adjusting screws what is this plate for?

[Gordon]

The advance timing is regulated by the spring rate of the two springs on the advancer unit, so you cannot individually set the idle and advance timing.  You can, however, adjust the advance timing by changing the spring rate of the advance unit springs. 

[Scrubs]

Thanks Gordon, That makes sense.

any idea what the screws that the red arrows are pointing too are for (although one is hidden)
I usually use the one circled in green to set the gap same as 1st set of points

[Donzon]

any idea what the screws that the red arrows are pointing too are for (although one is hidden)
I usually use the one circled in green to set the gap same as 1st set of points

Loosen those to set the timing for the 2 and 3 cylinders, it needs to be set as well.

Don

[eurban]

There is a stop that keeps the timing from advancing beyond a certain point.  Rotate your advance mechanism by hand and you will see how the stop works.  The stop and the "stopee" can wear over time and sometimes the discrepency you describe can be the result. It is possible to bend the parts a bit to compensate but be careful.  If your engine is running well enough then you might just want to stop worrying about things but if you are hearing or seeing signs of pinging, predetonation then you might want to simply set your timing so that it is correct at full advance (you spend most of your time at this range)

[Bodi]

The advancer spring tension sets the RPM that the advance happens at. The actual degrees of advance is set mechanically and isn't really adjustable, as eurban says you can bend stuff and change it but if it's working otherwise I would leave it be.
The best thing is to set your timing - using a timing strobe - at the advance mark (at about 3K RPM so you have full advance!). Let the idle timing be whatever it is, if you have idling issues that are fixed when you set the idle timing right at "F" then try to adjust the advancer - but idle advance is not at particularly critical, it just has to be way retarded from the ideal advance at higher RPM.
The advanced timimg is critical, and the advance timing mark is Honda's compromise between performance and preignition. For a bit better power you can advance it a bit more... if you use good gas and everything is in good shape this is OK. Too much advance will give "knock" or preignition, this is very hard to hear or feel on a bike but will melt your piston crowns in time. That's why I recommend setting timing at full advance - you do basically 100% of your riding at full advance, and a worn advancer that has more travel than spec will give you too much advance at speed (potentially dangerously too much).

[Bob Wessner]

The reference to 'over advance' rang a bell and is mentioned in other replies as well. If you check this link, there's further detail, particularly in para. six which starts with, "A strobelight is essential..."

http://www.motorcycleproject.com/motorcycle/text/sohcign.html